Topic8 Genetic Fingerprinting Flashcards
What is Genetic Fingerprinting?
Genetic Fingerprinting is the analysis of VNTR DNA fragments.
Genetic Fingerprinting is the examination of VNTRs
(VNTRs is Variable number tandem repeats)
What does VNTRs mean and what is it?
Variable number tandem repeats.
Long sequences of DNA bases that repeat over and don’t code for anything
Describe when Two individuals having same VNTRs
Having same VNTRS very low however more closely related you are similar the VNTRs
What are all the stages in Genetic Fingerprinting?
1.Collect and Extraction
2.Digestion
3.Separation
4.Hybridisation
5.Development
6.Analysis
What happens in Collection and Extraction in Genetic Fingerprinting?
The smallest Sample only for DNA can be collected for genetic fingerprinting.
If sample small then PCR used to amplify DNA
What is the digestion stage in Genetic Fingerprinting and how does it occur?
Digestion: enzyme to cut up large sample into all of the different VNTRs
Restriction Endonuclease are added to cut the DNA into smaller fragments.
Whole length of VNTRs maintained
What is the separation step in Genetic Fingerprinting?
What are the first steps in Genetic Fingerprinting?
[Hint:Describe the gel distribution of charge]
Seperation all VNTRs into analysing VNTRs which they have.
DNA sample loaded into small wells in agar gel.
The gel placed in buffer liquid with electrical voltage applied
One end of the gel nearest DNA negative charge
End far away from well has positive charge
In Separation how does the DNA move?
What is the second step in Separation called?
DNA negatively charged so DNA samples move through gel towards positive end of gel.
Second step is Gel Electrophoresis
What is the second step called in Separation?
What occurs and what does it do?
Gel Electrophoresis
Agar gel creates resistance for moving DNA.
Smaller Pieces of DNA move faster and further along.
It causes different length of VNTRs(DNA) are separated.
An Alkaline is then added to separated the double strands of DNA
What is Hybridisation?
Different DNA probes mixed with single stranded DNA VNTRs on the agar gel for them to bind- Hybridise-
What is needed for Hybridisatio step in Genetic FingerPrinting?
DNA probes short single stranded piece of DNA complementary in base sequence to VNTRs
Probes are Radioactively or Fluorescently labelled
What is the first step in Development stage in Genetic Fingerprinting?
Agar gel will shrink and crack as it dries after being taken out of liquid therefore VNTRs and DNA probes are
Transferred to a Nylon Sheet
In development stage in Genetic FingerPrinting what is used when using a RadioActive gene and if you use Fluorescence Probes?
RadioActive Gene: VNTRs and DNA probes transferred to NylonSheet which is exposed to X-Rays to visualise position of RadioActive gene
Fluorescence Probes: U.V light used
DNA probes attach to the VNTRs glow a green yellow colour.
What is the Analysis stage in Genetic FingerPrinting?
What is the paternity test?
The position of the DNA bands are compared.
In paternity test- Compare the bands of VNTRs
